JP2002310581A - Plate type heat pipe and its mounting method - Google Patents

Abstract

(57) Abstract: A heat pipe provided with a highly airtight container having long-term reliability without reducing the strength of a plate material of the heat pipe, and a mounting method thereof. The plate comprises a plate material to which at least one element to be cooled is thermally connected, and another plate material combined with the plate material to form a cavity therein, wherein the plate material and the another plate material are provided. A plate-type heat pipe provided with a highly airtight container in which a working fluid is sealed, which is formed by pressing an outer peripheral portion in which the above is combined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to electric / electronic parts,
For example, the present invention relates to a method for manufacturing a plate-type heat pipe suitable for cooling an element to be cooled having a high calorific value, such as a semiconductor chip, and a method for mounting the same.

[0002]

2. Description of the Related Art Electronic components such as semiconductor elements mounted on electric / electronic devices such as CPUs, laser diodes, and power transistors of personal computers are inevitable to generate some heat due to their use. Is becoming a major technical challenge. As a method of cooling an electric / electronic element requiring cooling (hereinafter, referred to as a “cooled element”), for example, a method of lowering the temperature of the air in the equipment housing by attaching a fan to the equipment, or cooling the cooled element. A method of directly cooling the element to be cooled by attaching a body is typically known.

As a cooling body attached to the element to be cooled, for example, a plate made of a material having excellent heat conductivity, such as a copper material or an aluminum material, or a plate-type heat pipe is often used. The plate-type heat pipe is a plate-shaped heat pipe, and may also be called a flat heat pipe or a flat plate heat pipe. Hereinafter, it is referred to as a plate-type heat pipe.

[0004] The heat pipe will be briefly described. The heat pipe is a container having a cavity, and a working fluid (working fluid) is sealed in the cavity. The cavity is evacuated to facilitate the evaporation of the working fluid. As the working fluid, water, alcohol, CFC substitute, or the like is used in consideration of compatibility with the material of the container.

[0005] The operation of the heat pipe will be briefly described. That is, on the heat absorbing side of the heat pipe, the working fluid evaporates due to the heat transmitted through the material of the container (container) constituting the heat pipe, and the vapor moves to the heat radiation side of the heat pipe. On the heat radiation side, the vapor of the working fluid is cooled and returns to the liquid state again. Then, the working fluid that has returned to the liquid phase moves (recirculates) to the heat absorbing side again.
Heat is transferred by such phase transformation and movement of the working fluid.

[0006] The working fluid is recirculated by gravity or capillary action. In the case of a gravity-type heat pipe, the working fluid is recirculated by disposing the heat absorbing portion below the heat radiating portion. In the case of a heat pipe that recirculates the working fluid by capillary action, a groove is provided on the inner wall of the cavity, or a wick such as a metal mesh or a porous body is inserted inside the cavity, and the working fluid is formed by the capillary action due to the groove or wick. Reflux. As described above, in the heat pipe, a large amount of heat is transported by the phase transformation and movement of the working fluid sealed in the closed cavity of the heat pipe. Of course, some heat is carried by conducting heat through the containers that make up the heat pipe,
The amount is relatively small.

A component to be cooled is thermally connected to the above-mentioned heat absorbing side. On the heat radiation side, for example, a heat radiation fin is attached. With such a configuration, most of the heat of the component to be cooled is moved by the heat pipe and dissipated from the heat radiation fin. By the way, in the case of a plate-type heat pipe, there is an advantage that it is easy to connect the component to be cooled and the heat pipe due to the feature of its shape. That is, by bringing a component to be cooled, such as a semiconductor element, into contact with the main surface of the heat pipe, it can be brought into contact with a relatively large area. In addition, contact between the part to be cooled and the heat pipe
In some cases, heat transfer grease or heat transfer rubber may be sandwiched between the two,
The two may be joined by soldering or the like. In addition, on the surface opposite to the main surface of the plate type heat pipe with which the component to be cooled is in contact, fins and heat sinks for heat dissipation,
It is good to attach a fan etc. With such an arrangement, a cooling structure that is excellent in space efficiency can be realized.

In particular, in recent years, the heat generation density has tended to increase due to the high integration and high speed of the CPU, and the performance of the heat pipe has not only reduced the heat transfer but also reduced the high-density heat flux. The need to spread heat must also be met. Further, since the boards on which the CPUs are mounted are arranged in various directions, the performance must be exhibited in a state where the heat pipes are arranged in various directions. Therefore, a heat transfer block having a function of diffusing at a low density is arranged in a portion where a heating element having a high heat generation density contacts inside the heat pipe, or a wick such as a metal mesh or a porous body is appropriately arranged. Accordingly, it is necessary to prevent the occurrence of dryout (meaning that the supply of the working fluid cannot catch up with the evaporation in the heat absorbing portion, and the heat absorbing portion is completely dried and the operation as the heat pipe does not continue). . The heat transfer block may have another component inserted therein or may be formed as a member integral with the container.

[0009]

The container of the plate-type heat pipe is formed by joining two plate-like members formed by pressing or the like by brazing or the like (for example, Japanese Patent Application No. Hei 8-3).
12980), and a method of enclosing and joining by folding (Japanese Patent Application No. 10-09781). But,
When brazing (or soldering) is used as a main means of joining as a joining method of members for forming a container of a closed body, compatibility between brazing material and working fluid, or depending on the type of flux, There is a problem that the performance of the heat pipe tends to deteriorate. In order to improve the compatibility between the brazing material and the working fluid, it is desirable to use a brazing material having a low impurity content and a composition close to that of the base material. , And there is a problem that the base material is annealed to lower the strength. Furthermore, the time required for processing and the cost increase due to the use of other members such as brazing material are inevitable.

On the other hand, in the case of sealing by folding, there is a problem that the outer shape is restricted and cannot be applied unless the shape is simple. Further, according to this method, since it is difficult to join the members metallically, there is a problem that the sealing property cannot be maintained for a long time, that is, the long-term reliability of the heat pipe is impaired. Therefore, it is difficult to manufacture a highly airtight sealing body for a heat pipe by simply using this technique. Accordingly, an object of the present invention is to provide a heat pipe provided with a highly airtight container having long-term reliability without reducing the strength of a plate material of the heat pipe, and a mounting method thereof.

[0011]

Means for Solving the Problems The inventor has made intensive studies to solve the above-mentioned conventional problems. As a result, a plate material on which the element to be cooled is thermally connected,
When the outer peripheral portion combined with another plate material that forms a cavity inside by combining it is pressed down while maintaining a clean state, a new surface is formed on the joining surface of both plate materials, and the new surface is pressed together. As a result, it was found that a heat pipe provided with a metal-sealed container having excellent hermeticity and without deterioration in strength can be produced.

[0012] The present invention has been made based on the above-mentioned findings, and the first aspect of the plate-type heat pipe of the present invention.
The aspect of the present invention comprises a plate material to which at least one element to be cooled is thermally connected to a surface thereof, and another plate material combined with the plate material to form a cavity therein, wherein the plate material and the another plate material Is a plate-shaped heat pipe provided with a highly airtight container in which a working fluid is sealed, formed by pressing an outer peripheral portion of the heat pipe.

A second aspect of the plate-type heat pipe according to the present invention is a plate-type heat pipe characterized in that the outer peripheral portion of the plate material and the another plate material are pressed by metal joining by reduction.

According to a third aspect of the plate-type heat pipe of the present invention, a new surface is formed on each joint surface of the outer peripheral portion of the plate material and the another plate material by the pressing, and the new surfaces are pressed together to form a metal. It is a plate type heat pipe to be joined.

[0015] A fourth aspect of the plate-type heat pipe of the present invention is a plate-type heat pipe in which the plate and the another plate are made of a clad plate.

According to a fifth aspect of the plate heat pipe of the present invention, at least one of the plate material and the another plate material is subjected to deep drawing, stretch forming, or forging,
It is a plate-shaped heat pipe forming the hollow part.

A sixth aspect of the plate-type heat pipe according to the present invention is a plate-type heat pipe, wherein a projection is formed at a portion of the plate material to which the at least one element to be cooled is thermally connected. is there.

According to a seventh aspect of the plate type heat pipe of the present invention, at least one element to be cooled is thermally connected to the surface of the plate type heat pipe, and another plate as another main surface is provided. Plate material, sandwiched between the plate material and the another plate material,
Forming a hollow portion inside, comprising a frame-shaped member as a side surface, formed by pressing the outer peripheral portion of the plate material and the another plate material sandwiching the frame-shaped member, the working fluid in the inside thereof It is a plate-type heat pipe provided with a sealed airtight container.

An eighth aspect of the plate-type heat pipe according to the present invention is characterized in that the outer peripheral portions of the plate member and the another plate member sandwiching the frame-like member are pressed by metal joining by pressing down. , A plate-type heat pipe.

According to a ninth aspect of the plate-type heat pipe of the present invention, a new surface is formed on each joint surface of the outer peripheral portions of the plate material and the another plate material and the joint surface of the frame-shaped member by the reduction. Then, a plate-shaped heat pipe is formed in which the new surfaces are pressed and metal-bonded.

A tenth aspect of the plate-type heat pipe according to the present invention is a plate-type heat pipe in which a wick member is provided in the airtight container.

An eleventh aspect of the plate type heat pipe of the present invention is a plate type heat pipe in which a heat conductive member is provided in the hermetic container.

According to a twelfth aspect of the present invention, there is provided a plate-type heat pipe in which the heat conductive member is formed integrally with the plate or another plate.

A thirteenth aspect of the plate type heat pipe of the present invention is a plate type heat pipe in which the pressed outer peripheral portion is further brazed or soldered.

According to a fourteenth aspect of the present invention, there is provided a plate-type heat pipe in which the press-contacted outer peripheral portion is further welded.

According to a first aspect of the mounting method of the present invention, a board on which the element to be cooled is mounted is joined to the main surface of the above-mentioned plate-type heat pipe, and a heat sink is joined to the other main surface. A method for mounting a cooled element and a heat pipe, wherein a fan for blowing air to the heat sink is provided at a predetermined position.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION The plate type heat pipe of the present invention
A plate material on which at least one element to be cooled is thermally connected, and another plate material combined with the plate material to form a cavity therein, and an outer peripheral portion obtained by combining the plate material with another plate material is formed. This is a plate-type heat pipe provided with a highly airtight container in which a working fluid is sealed, which is formed by pressing. The above-described bonding is performed by metal bonding by reduction. That is, by the above-described reduction, a new surface is formed on each joining surface of the outer peripheral portion of the plate material and another plate material, and the new surfaces are pressed and metal-joined.

FIG. 1 is a view for explaining an example of pressure welding of an outer peripheral portion of a plate type heat pipe according to the present invention. FIG.
As shown in (a), the pressure welding in the present invention firstly
Two plate members forming the main surface of the plate-type heat pipe, that is,
The outer peripheral portion 4 of the upper plate 1 and the lower plate 2 is overlapped. Next, as shown in FIG. 1B, the outer peripheral portion 4 of the upper plate 1 and the lower plate 2 thus superimposed is pressed down in both directions, for example, from above and below. The amount of reduction is the material of the upper and lower plates, the surface condition, and the environment in which the material is reduced (in vacuum, in air)
Depends on For example, when the surfaces of both plate materials are cleaned and reduced in a vacuum, the amount of reduction may be 2 to 3%, and when reduced in the atmosphere, at least 30%.
%, Preferably 50% or more.

As shown in FIG. 1 (c), the joining surfaces are overlapped and pressed down to expose a new surface (a clean metal surface having no oxide film or adsorption film) on the deformed portion. The new surfaces are pressed together to form a metal joint, 2
The members are joined. In this case, the metal-bonded portion is a portion indicated by a dotted line in FIG. The metal-bonded member is strongly metal-bonded so that when a force is applied in the direction in which the two plate materials are peeled off, it does not separate into the original plate material and the base material breaks at the joint, and the container is airtight. Is excellent. The temperature at the time of pressing may be any temperature lower than the melting point of the plate material, and may be, for example, room temperature.

The press-contact method may be any method as long as the joint is plastically deformed, and various working methods such as flat pressing, forging, drawing, and ironing can be used. The processing method is selected depending on the external shape and internal structure of the heat pipe. Before joining, it is necessary to clean the joining surface as much as possible to remove oxides, hydroxides, organic substances, and other coatings and deposits. Examples of the method include mechanical methods such as brushing and sanding. And chemical methods such as dry etching. During the period from cleaning of the surface to completion of the pressure welding, it is necessary to minimize the adhesion of dust, moisture or oil, or the formation of an oxide film on the portion to be joined. For a short time, there is no problem in the air, for example, by brushing in the air, and immediately afterward, by flattening the joining surfaces together, it is possible to perform pressure welding. Alternatively, the joints of the members may be cleaned by plasma in a vacuum chamber, and pressed in the chamber while maintaining a vacuum or an inert atmosphere. In this case, the amount of reduction may be small.

FIG. 2 shows a plate-type heat pipe 1 according to the present invention.
FIG. 4 is a diagram for explaining one aspect. The plate-type heat pipe of the present invention includes a plate member 2 having at least one element to be cooled thermally connected to a surface thereof formed into a box shape, and a plate member 2.
Flat plate material 1 that is combined with
And a heat conductive block 6 and a wick 5 are arranged in the cavity. In this way, the outer peripheral portion 4 in which the heat conductive block and the wick are combined with the plate material 2 and the flat plate material 1 arranged in the cavity portion is pressed down, and the outer peripheral portion 4 of the plate material 2 and the outer peripheral portion 4 of the flat plate material 1 are respectively reduced. A new surface is formed on the joining surface, and the formed new surfaces are pressed and metal-joined.

At this time, without pressing the hollow part of the container, using a mold that presses only the outer peripheral part, the outer peripheral part is crushed to perform pressure contact, and a container (sealed body) having excellent airtightness is obtained. Can be formed. That is, the metal-bonded portion in this case is a portion indicated by a dotted line in FIG. In addition, the member joined to the metal does not separate into the original plate material when a force is applied in the direction of peeling the two plate materials,
The metal is firmly joined so that the base material is broken at the joint, and the container has excellent airtightness. Although not shown in the figure, a plate-type heat pipe is manufactured by providing a port for liquid injection and degassing in a part of the container, injecting working fluid (pure water), and degassing. can do.

FIG. 3 is a view for explaining another embodiment of the plate type heat pipe of the present invention. In this embodiment, as shown in FIG. 3, the outer peripheral portion pressed as shown in FIG. 1 is further brazed or soldered. Reinforce the mechanical strength by reinforcing the joint of the pressed outer periphery by brazing or soldering,
And / or has an effect of preventing corrosion of the bonding interface. Since the outer peripheral portion is locally deformed by the pressure welding, the mechanical strength of the thinned portion may be reduced. When the hermetically sealed container is damaged due to a decrease in mechanical strength, the working fluid of the heat pipe flows out or the atmosphere flows into the container, leading to a long-term deterioration of the heat pipe performance. On the other hand, when the solder penetrates into the inner surface of the heat pipe, the working fluid (for example, pure water) reacts with the solder material to generate gas inside the container, leading to a long-term deterioration in the performance of the heat pipe.

In the plate-type heat pipe of the present invention, since the outer peripheral portion is hermetically sealed in a state of excellent airtightness by pressure welding, the outer peripheral portion is reinforced by brazing or soldering from the outside from outside. However, the solder or solder does not enter the inner surface of the heat pipe and does not come into contact with the working fluid. In FIG. 3, the outer peripheral pressure contact portion is denoted by A,
The soldered portion is indicated by B. As a brazing or soldering method, a vacuum furnace, an atmosphere furnace, a torch, a soldering iron, or the like can be used. These methods are appropriately selected depending on the material, shape and size of the heat pipe container, the thermal performance required for the heat pipe, the interaction with the working fluid, and the like.

FIG. 4 is a view for explaining another embodiment of the plate type heat pipe of the present invention. In this embodiment, as shown in FIG. 4, welding is further performed on the outer peripheral portion pressed as shown in FIG. 1. Even if mechanical strength such as pressure resistance is sufficiently obtained by pressure welding, sealing is not perfect,
If there is a possibility of minute leakage, welding may be used together. Even in that case, most of the bonding strength is carried by pressure welding. In FIG. 4, the press contact portion is indicated by A, and the welded portion is indicated by C. As the welding method, welding methods such as TIG welding, plasma welding, laser welding, and electron beam welding are possible. These welding methods are based on the material, shape and size of the heat pipe container, the thermal performance required for the heat pipe,
It is appropriately selected depending on the interaction with the working fluid and the like.

FIG. 5 is a view for explaining another embodiment of the plate type heat pipe of the present invention. In the plate-type heat pipe of this embodiment, as shown in FIG. 5, the main parts forming the hermetic body are constituted by two plate members 1 and 2 constituting both upper and lower main surfaces of the plate-type heat pipe. ing. In this case, as shown in FIG. 5, in order to form a space (hollow portion) inside, at least one plate material (2 in the figure)
It needs to be formed to have a predetermined height. The configuration of this embodiment has the least number of members and is easy to process.

FIG. 6 is a view for explaining another embodiment of the plate type heat pipe of the present invention. In the plate type heat pipe of this embodiment, the heat conductive block is disposed inside the container. As shown in FIG. 6, a block-shaped portion C can be integrally formed on one of the two plate members 2 by forging. Thereby, there are advantages that the number of members is reduced and heat conduction is improved as compared with inserting a heat conductive block as a separate member.

As another embodiment of the plate-type heat pipe of the present invention, a plate as one main surface to which at least one element to be cooled is thermally connected, and another plate as another main surface. And a frame-shaped member as a side surface, which is sandwiched between a plate material and another plate material to form a cavity therein.
2. Description of the Related Art There is a plate-type heat pipe provided with a highly airtight container in which a working fluid is sealed, which is formed by pressing an outer peripheral portion of a plate member sandwiching a frame member and another plate member.

The outer peripheral portions of the plate member sandwiching the frame-like member and another plate member are pressed by metal bonding by pressing. That is, by the above-described reduction, a new surface is formed on each of the joining surfaces of the outer peripheral portion of the plate material and another plate material and the joining surface of the frame-shaped member, and the new surfaces are pressed and metal-joined.

FIG. 7 is a view for explaining the members constituting the plate-type heat pipe according to the present invention. As shown in FIG. 7, in this embodiment, the main members forming the container (sealed body) are two plate members 1 and 2 and two plate members forming the upper and lower main surfaces of the plate-type heat pipe. Sandwiched between
It comprises a frame-shaped member 3 as a side surface which forms a cavity inside.

FIG. 8 is a view for explaining another example of the pressure welding of the outer peripheral portion of the plate-type heat pipe according to the present invention. FIG.
As shown in (a), the pressure welding in the present invention firstly
Two plate members forming the main surface of the plate-type heat pipe, that is,
Between the upper plate 1 and the lower plate 2, a frame member 3 as a side surface, which forms a cavity inside, is sandwiched.
And the outer peripheral portion 4 of the upper plate 1 and the lower plate 2 are overlapped. Next, as shown in FIG. 8 (b), the outer peripheral portion 4 of the upper plate member 1, the frame-shaped member 3, and the outer peripheral portion 4 of the lower plate member 2 overlapped in this manner are vertically lowered as shown by the hatched portions. I do. The amount of reduction differs depending on the material of the upper plate material and the lower plate material, the state of the surface, and the environment in which the material is reduced (in vacuum, in air).
For example, when the surfaces of both plates are cleaned and reduced in a vacuum, the amount of reduction may be 2-3%, and when reduced in the atmosphere, at least 30%, preferably 5%.
It is necessary to reduce the thickness so as to give a thickness reduction of 0% or more.

As shown in FIG. 8C, the joining surfaces of the upper plate member 1, the frame-shaped member 3, and the lower plate member 2 are overlapped with each other and pressed down in the vertical direction so that the deformed portion has a new surface (oxidized surface). Exposing a clean metal surface without film or adsorption film)
The new surfaces are pressed together to form a metal joint, and the upper plate, the frame member, and the lower plate are joined. The metal joint in this case is indicated by dotted lines between the upper plate member and the frame member and between the frame member and the lower plate member, as shown in FIG. When a force is applied in the direction in which these plate materials are peeled off, they are not separated into the original plate material, but are strongly metal-joined so that the base material is broken at the joint, and the container is excellent in airtightness. The temperature at the time of pressing and the pressing method are the same as those described in the embodiment of FIG. In this case, as shown in FIG. 8, three members, an upper plate member, a frame-shaped member and a lower plate member, are simultaneously pressed. The configuration of the above-described members is appropriately selected depending on the required shape, thermal performance, cost, and the like.

FIG. 9 is a view for explaining another embodiment of the plate type heat pipe of the present invention. In the plate-type heat pipe of this embodiment, as shown in FIG. 9, a projection E for efficiently cooling the element to be cooled is integrally formed on one of the plate members to which the element to be cooled is thermally connected. Have been. The shape of the projection depends on the arrangement of the element to be cooled and other components mounted on the substrate, and the like.

FIG. 10 is a view for explaining another embodiment of the plate type heat pipe of the present invention. Usually, the material of the container is composed of only one kind of material, such as copper for copper and aluminum for aluminum. In the embodiment shown in FIG. 10, the cladding materials 11 and 12 are used for the plate material. When a clad material is used, the clad material 11,
The material 8 forming the inner surface side of the 12 containers is made of a material having high compatibility with the working fluid, for example, copper, and the material 9 forming the outer surface side is made according to the requirements of mechanical strength and appearance. In addition, a material having high strength, low cost, light weight, and the like, for example, aluminum can be used, and the degree of freedom of design can be increased and the cost can be reduced.

Further, according to the mounting method of the present invention, the board on which the element to be cooled is mounted is joined to the main surface of the plate-type heat pipe, and the heat sink is joined to another main surface.
This is a heat pipe mounting method in which a fan that blows air to a heat sink is provided at a predetermined position. The present invention will be described in more detail by way of examples.

[0046]

EXAMPLE 1 As shown in FIG. 2, a lower plate material 2 and a flat upper plate material 1 each formed into a box shape by using a pure copper plate having a thickness of 1 mm were prepared. Next, the outer peripheral portion 4 of the upper plate member 1 and the lower plate member 2 are combined, and a pure copper heat conductive block 6 and a pure copper wick 5 having an opening 13 for accommodating the heat conductive block are formed therein. Was placed. Before assembling, the outer peripheral surface where the upper plate 1 and the lower plate 2 were joined was cleaned by brushing to remove oxides, hydroxides, organic substances, and other coatings and deposits.

The outer plate 1 and the lower plate 2 were combined while the surface of the outer peripheral portion thus joined was kept in a clean state, and the outer peripheral portion was lowered at room temperature in the air. The rolling reduction at that time was 70%. That is, pressure contact was performed by crushing only the outer peripheral portion using a mold that presses only the outer peripheral portion without pressing the hollow portion of the container. By pressing the outer peripheral portion in this manner, a container having an overall size of 70 mm × 90 mm × 7 mm and having excellent airtightness, in which the heat conductive block and the wick were arranged, was produced. In addition, a part of the container is provided with a port for liquid injection and degassing, working fluid (pure water) is injected, degassed,
A plate-type heat pipe was manufactured.

The plate-shaped heat pipe manufactured as described above
The strength and airtightness of the welded joint were tested.
Of course, the strength is peeled off at 140 kPa in the pressure test.
Strength, and airtightness is not
And the leak amount 1 × 10^-9Pa ・ m ^Three/ S or less.

Example 2 As shown in FIG. 10, a box-shaped press-molding was performed using a 1.0 mm-thick clad plate made of a pure copper layer having a thickness of 0.2 mm and an aluminum layer having a thickness of 0.8 mm. A lower plate 12 and a flat upper plate 11 were prepared. Next, the outer peripheral portion 4 of the upper plate 11 and the lower plate 12
, So that the inner surface side of the container becomes a pure copper layer,
A pure copper heat conductive block 6 and a pure copper wick 5 having an opening 13 for accommodating the heat conductive block as shown in FIG. 2 were arranged in the container. Before assembling, the outer peripheral surface where the upper plate 11 and the lower plate 12 were joined was cleaned by brushing to remove oxides, hydroxides, organic substances, and other coatings and deposits.

The outer plate 11 and the lower plate 12 were combined while the surface of the outer peripheral portion thus joined was kept in a clean state, and the outer peripheral portion was pressed down at room temperature in a vacuum. The rolling reduction at that time was 50%. That is, pressure contact was performed by crushing only the outer peripheral portion using a mold that presses only the outer peripheral portion without pressing the hollow portion of the container. By pressing the outer peripheral portion in this manner, a container having an overall size of 70 mm × 90 mm × 7 mm and made of aluminum on the outside and having excellent airtightness, in which the heat conductive block and the wick were arranged, was produced. Further, a port for liquid injection and deaeration was provided in a part of the container, a working fluid (pure water) was injected, and the container was deaerated to produce a plate-type heat pipe.

When the strength and airtightness of the pressure-welded joint of the plate-type heat pipe manufactured as described above were tested, the strength was such that it could not be peeled off at 140 kPa in the pressure test, and the airtightness was He. In the leak test,
The leak amount was 1 × 10 ⁻⁹ Pa · m ³ / s or less. As described above, the plate-type heat pipe of the present invention maintains the plate material forming the container at a predetermined strength, has high joining strength, and has high airtightness.

[0052]

According to the present invention, it is possible to provide a plate-type heat pipe having high joining strength, high airtightness, and excellent long-term reliability without reducing the strength of the plate material forming the container. Further, according to the present invention, the number of members constituting the heat pipe is reduced, the manufacturing process is simplified, the plate heat pipe is cooled at a low cost and high reliability, and cools a high heat generation element such as a semiconductor element. Can be manufactured.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of pressure welding of an outer peripheral portion of a plate-type heat pipe according to the present invention.

FIG. 2 is a diagram illustrating one embodiment of a plate-type heat pipe according to the present invention.

FIG. 3 is another plate-type heat pipe of the present invention.
FIG. 4 is a diagram for explaining one aspect.

FIG. 4 is another plate-type heat pipe of the present invention.
FIG. 4 is a diagram for explaining one aspect.

FIG. 5 is another plate heat pipe of the present invention.
FIG. 4 is a diagram for explaining one aspect.

FIG. 6 is another plate-type heat pipe of the present invention.
FIG. 4 is a diagram for explaining one aspect.

FIG. 7 is a diagram for explaining members constituting a plate-type heat pipe according to the present invention.

FIG. 8 is a view for explaining another example of the pressure welding of the outer peripheral portion of the plate-type heat pipe according to the present invention.

FIG. 9 shows another example of the plate-type heat pipe of the present invention.
FIG. 4 is a diagram for explaining one aspect.

FIG. 10 is a diagram illustrating another embodiment of the plate heat pipe of the present invention.

[Explanation of symbols]

 1. Board material 2. Plate material 3. Frame member 4. Outer part 5. Wick 6. 6. Thermal conductive block Cavity 8. 8. Material forming inner surface side 10. Material forming outer surface side Clad plate material 12. Clad sheet material

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) B23K 1/00 330 B23K 1/00 330Z F25D 9/00 F25D 9/00 D H01L 23/427 H05K 7/20 H H05K 7 / 20 R B21D 53/04 Z // B21D 53/04 B23K 101: 12 B23K 101: 12 H01L 23/46 B (72) Inventor Yuichi Kimura 2-6-1 Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd. Company F term (reference) 3L044 CA13 DD03 EA03 4E087 BA19 CA51 HB06 HB15 5E322 BB10 DB10 5F036 AA01 BB35 BB60

Claims (15)

[Claims] 1. A plate material having at least one element to be cooled thermally connected to a surface thereof, and another plate material combined with the plate material to form a cavity therein, wherein the plate material and the another one are formed. A plate-type heat pipe provided with a highly airtight container in which a working fluid is sealed, which is formed by pressing an outer peripheral portion of a combination of plate materials. 2. The plate-type heat pipe according to claim 1, wherein the pressure contact between the outer periphery of the plate material and the another plate material is performed by metal joining by pressing down. 3. The plate mold according to claim 2, wherein the reduced surface forms a new surface on a joining surface of each of the outer peripheral portions of the plate material and the another plate material, and the new surfaces are press-bonded and metal-joined. heat pipe. 4. The plate-type heat pipe according to claim 1, wherein said plate member and said another plate member are made of a clad plate member. 5. The method according to claim 1, wherein at least one of the plate material and the another plate material is subjected to deep drawing, stretch forming, or forging to form the hollow portion. The plate-shaped heat pipe as described. 6. A protruding portion is formed on a portion of the plate material to which the at least one element to be cooled is thermally connected.
The plate type heat pipe according to claim 1. 7. A plate as one main surface to which at least one element to be cooled is thermally connected to a surface thereof, another plate as another main surface, and between the plate and the another plate. Sandwiched between, to form a cavity inside, consisting of a frame-shaped member as a side surface, formed by pressing the outer periphery of the plate material and another plate material sandwiching the frame-shaped member, the A plate-type heat pipe equipped with a highly airtight container with a working fluid sealed inside. 8. The plate-type heat pipe according to claim 7, wherein the outer peripheral portions of the plate member and the another plate member sandwiching the frame-shaped member are pressed by metal joining by pressing down. 9. A new surface is formed on the joint surface of each of the outer peripheral portions of the plate material and the another plate material and the joint surface of the frame-shaped member by the pressing, and the new surface surfaces are press-bonded and metal-joined. The plate-type heat pipe according to claim 8, wherein 10. The plate type heat pipe according to claim 1, wherein a wick member is provided in the airtight container. 11. The plate type heat pipe according to claim 1, wherein a heat conductive member is provided in the airtight container. 12. The plate type heat pipe according to claim 11, wherein said heat conductive member is formed integrally with said plate member or said another plate member. 13. The plate-type heat pipe according to claim 1, wherein the outer peripheral portion that has been pressed is further brazed or soldered. 14. The plate-type heat pipe according to claim 1, wherein welding is further performed on the pressed outer peripheral portion. 15. A plate having a cooled element mounted thereon is joined to the main surface of the plate-type heat pipe according to claim 1, and a heat sink is joined to the another main surface. Further, a mounting method of a plate-type heat pipe, wherein a fan for blowing air to the heat sink is provided at a predetermined position.